May 27:  The Southern road reaches Hudson from Adrian.  [MCR-75]

July 4:  Detroit & Pontiac Railroad finally reaches Pontiac from Birmingham.  The track was a strap rail spiked to wooden stringers.  [HWC][MDOT/AAD]   [MCR-75] dates this extension as Autumn of 1844.

September 25:  Southern line  reaches Hillsdale from Hudson.  68 total miles of track from Monroe.  [MCR-75/DWS/EMR4]  According to MCR-75, the State suspended building at Hillsdale until the road was sold to the Michigan Southern Railroad Company in 1846.  It appears that building was actually resumes west of Hillsdale in 1850.

Copper Mining boom begins in the Upper Peninsula, following reports from Dr. Douglas Houghton, the first State Geologist.  [MSL]

The Detroit & Pontiac Railroad begins using a passenger car which is iron sheathed on the bottom to prevent "snake heads" (rails) from popping up and injuring or killing passengers.  This continued to be a problem until iron rails were used.  [AAD]

A trip on the Central line from Detroit to Marshall takes 7 1/2 hours.  To continue to Chicago, the traveler boarded a stage coach which took him 90 more miles in 22 hours.  To complete the trip, the traveler then boarded a steamer and reached Chicago, the remaining 69 miles across the lake, in 6 hours.  Total time: 39 1/2 hours.  [AAD]